/* * linux/arch/arm/mm/copypage-v6.c * * Copyright (C) 2002 Deep Blue Solutions Ltd, All Rights Reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/init.h> #include <linux/spinlock.h> #include <linux/mm.h> #include <asm/page.h> #include <asm/pgtable.h> #include <asm/shmparam.h> #include <asm/tlbflush.h> #include <asm/cacheflush.h> #include "mm.h" #if SHMLBA > 16384 #error FIX ME #endif #define from_address (0xffff8000) #define to_address (0xffffc000) static DEFINE_SPINLOCK(v6_lock); /* * Copy the user page. No aliasing to deal with so we can just * attack the kernel's existing mapping of these pages. */ static void v6_copy_user_page_nonaliasing(void *kto, const void *kfrom, unsigned long vaddr) { copy_page(kto, kfrom); } /* * Clear the user page. No aliasing to deal with so we can just * attack the kernel's existing mapping of this page. */ static void v6_clear_user_page_nonaliasing(void *kaddr, unsigned long vaddr) { clear_page(kaddr); } /* * Copy the page, taking account of the cache colour. */ static void v6_copy_user_page_aliasing(void *kto, const void *kfrom, unsigned long vaddr) { unsigned int offset = CACHE_COLOUR(vaddr); unsigned long from, to; /* * Discard data in the kernel mapping for the new page. * FIXME: needs this MCRR to be supported. */ __asm__("mcrr p15, 0, %1, %0, c6 @ 0xec401f06" : : "r" (kto), "r" ((unsigned long)kto + PAGE_SIZE - L1_CACHE_BYTES) : "cc"); /* * Now copy the page using the same cache colour as the * pages ultimate destination. */ spin_lock(&v6_lock); set_pte(TOP_PTE(from_address) + offset, pfn_pte(__pa(kfrom) >> PAGE_SHIFT, PAGE_KERNEL)); set_pte(TOP_PTE(to_address) + offset, pfn_pte(__pa(kto) >> PAGE_SHIFT, PAGE_KERNEL)); from = from_address + (offset << PAGE_SHIFT); to = to_address + (offset << PAGE_SHIFT); flush_tlb_kernel_page(from); flush_tlb_kernel_page(to); copy_page((void *)to, (void *)from); spin_unlock(&v6_lock); } /* * Clear the user page. We need to deal with the aliasing issues, * so remap the kernel page into the same cache colour as the user * page. */ static void v6_clear_user_page_aliasing(void *kaddr, unsigned long vaddr) { unsigned int offset = CACHE_COLOUR(vaddr); unsigned long to = to_address + (offset << PAGE_SHIFT); /* * Discard data in the kernel mapping for the new page * FIXME: needs this MCRR to be supported. */ __asm__("mcrr p15, 0, %1, %0, c6 @ 0xec401f06" : : "r" (kaddr), "r" ((unsigned long)kaddr + PAGE_SIZE - L1_CACHE_BYTES) : "cc"); /* * Now clear the page using the same cache colour as * the pages ultimate destination. */ spin_lock(&v6_lock); set_pte(TOP_PTE(to_address) + offset, pfn_pte(__pa(kaddr) >> PAGE_SHIFT, PAGE_KERNEL)); flush_tlb_kernel_page(to); clear_page((void *)to); spin_unlock(&v6_lock); } struct cpu_user_fns v6_user_fns __initdata = { .cpu_clear_user_page = v6_clear_user_page_nonaliasing, .cpu_copy_user_page = v6_copy_user_page_nonaliasing, }; static int __init v6_userpage_init(void) { if (cache_is_vipt_aliasing()) { cpu_user.cpu_clear_user_page = v6_clear_user_page_aliasing; cpu_user.cpu_copy_user_page = v6_copy_user_page_aliasing; } return 0; } core_initcall(v6_userpage_init);